bogax

Someone posted a question about bit twiddling in one of the 6502.org forums that was part of the answer some interesting stuff there (one of the interesting things is a pointer in one of the forums to this forum ) I believe I saw that posted to comp.sys.cbm some years ago, don't remember where it was said to have come from. Don't you need a clc in there?

That will teach me not to type off the top of my head again! The bit would have to move through the carry, so it would probably end up with a similar routine as yours in the end. --Selgus here's what I think of as the "standard" way of moving a bit through the carry cmp #$80 ;copy the high bit to the carry rol but here's another way using addition (I'm going to be all cagey and not comment it, it's more fun that way ) ;swapnibbles asl adc #$80 rol asl adc #$80 rol